Mission To An Asteroid

Asteroids are much more accessable than Mars - as well as better potential resources and more strategically important (Mars won't hit Earth anytime soon).

The NASA JPL Center for Near Earth Object Studies has a Really Cool Accessable Near Earth Asteroid online mission planner.

Here's a mission to 99942 Apophis:

Next Arecibo approach

2020-10

Next Goldstone approach

2021-03

Launch date

2028-06-01

Estimated Diameter

200-893 m

Est Hectares

13 - 251

Total mission delta V

6.92 km/s

Total mission duration

322 days

Outbound flight time

225 days

Stay time

32 days

Inbound flight time

65 days

Earth departure dV

3.824 km/s

NEA arrival dV

2.032 km/s

NEA departure dV

0.435 km/s

Earth return dV

0.625 km/s

Entry speed

12 km/s

NHATS Trajectory ID

102090

If we miss that opportunity, we can go to 2001 CQ36 in 2031, a 282 day mission.